New alarms warn dolphins about shark nets
The dolphin pinger
New acoustic alarms are being trialled on Australia’s Gold Coast and Rainbow Beach north of the Sunshine Coast to help reduce the number of dolphins caught in shark control equipment.
The ‘pingers’, have been attached to six of the 11 shark nets on the Gold Coast and two of the three nets at Rainbow Beach.
Shark control program manager Jeff Krause, from the Queensland Boating and Fisheries Patrol, said no dolphins had been caught in these nets since the new pingers were put in place in April this year.
"As with any trial of this nature the pingers will be in place for some time so we can properly determine their effectiveness, but these early results are promising," Mr Krause said.
The alarms are developed by Fumunda Marine, a Sunshine Coast-based specialist marine mammal acoustic pinger manufacturer.
Director of Fumunda Marine, James Turner said earlier pingers were designed to target harbour porpoises, prevalent in the northern hemisphere.
"These new pingers work differently to the porpoise pingers and are designed specifically to alert dolphins to the presence of the shark nets. The earlier porpoise pingers do work on some dolphin species but these new pingers are more powerful and deliver a louder signal, as dolphin species are larger and more robust than porpoises.”
The pingers operate at 70kHz, which sits right in the best known middle hearing range of bottlenose and common dolphins, both of which are found in Queensland.
Mr Krause said while the main priority of the Shark Control Program was to improve safety for beachgoers, a range of measures were in place to reduce the number of marine animal entanglements. He also said, "Given we're expecting to see up to 16,000 whales migrating along the coast this season, it's important we continue to take preventative measures to help them avoid entanglements.
A volunteer whale observer program is in place on the Gold Coast and Sunshine Coast, whereby people living in high-rise buildings are trained to identify whale entanglements in shark control gear if they occur. Surveillance cameras are also mounted on buildings at the Gold Coast, Sunshine Coast and Rainbow Beach to help monitor and check reported marine animal entanglements.
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